The histological changes after tibial lengthening with metaphyseal osteotomywere observed in 30 goats.It was found that(1)a slow lengthening rate of 1 mm/d couldenable the tissues to adapt the mechanical traction and ...The histological changes after tibial lengthening with metaphyseal osteotomywere observed in 30 goats.It was found that(1)a slow lengthening rate of 1 mm/d couldenable the tissues to adapt the mechanical traction and consequently increase thelengthening limitation;(2)the newly-formed bone in the lengthened area might be due to acombined osteogenesis of endochondral,intramembranous,and fibrous tissue ossification;and(3)the osteogenetic process could be distinguished into 3 stages as hemorrhage andorganization of the hematocele,callus formation,and remodelling of the newly-formedbones.展开更多
Four tibiae removed from 30-40 years males, who died of accidents in less than 12 hours, were os- teomized at medium part. Then these tibiae were fixed by an unilateral hooked-sulcated external fixator (UHSEF), and th...Four tibiae removed from 30-40 years males, who died of accidents in less than 12 hours, were os- teomized at medium part. Then these tibiae were fixed by an unilateral hooked-sulcated external fixator (UHSEF), and the bone-fixator system was used as a model of external fixation of tibial fracture. The axial compression, distraction, torsion, antero-posterior and lateral bending rigidly and the strain of the pins were determined in this system. Based on the results, we found that compared with the configuration of four paralled pins, the rigidity of the fan-like configuraton didn’t decrease significantly if the angle between lateral and medium pins was less than 45’. But the reverse was true when the frame separation increased from 5 to 8 cm. What’ more, the pin strain decreased if the rigidity of the system was improved. These data provided a theoretical basis of biomechanics for the improvement of UHSEF.展开更多
文摘The histological changes after tibial lengthening with metaphyseal osteotomywere observed in 30 goats.It was found that(1)a slow lengthening rate of 1 mm/d couldenable the tissues to adapt the mechanical traction and consequently increase thelengthening limitation;(2)the newly-formed bone in the lengthened area might be due to acombined osteogenesis of endochondral,intramembranous,and fibrous tissue ossification;and(3)the osteogenetic process could be distinguished into 3 stages as hemorrhage andorganization of the hematocele,callus formation,and remodelling of the newly-formedbones.
基金This work was supported by Wuhan science & Technolgy Committee
文摘Four tibiae removed from 30-40 years males, who died of accidents in less than 12 hours, were os- teomized at medium part. Then these tibiae were fixed by an unilateral hooked-sulcated external fixator (UHSEF), and the bone-fixator system was used as a model of external fixation of tibial fracture. The axial compression, distraction, torsion, antero-posterior and lateral bending rigidly and the strain of the pins were determined in this system. Based on the results, we found that compared with the configuration of four paralled pins, the rigidity of the fan-like configuraton didn’t decrease significantly if the angle between lateral and medium pins was less than 45’. But the reverse was true when the frame separation increased from 5 to 8 cm. What’ more, the pin strain decreased if the rigidity of the system was improved. These data provided a theoretical basis of biomechanics for the improvement of UHSEF.
